Phoenix Contact 2903281 General Purpose Relay DPDT 24VDC

Part Overview

The Phoenix Contact 2903281 is a general purpose relay with DPDT (2 Form C) contact configuration, designed for 24VDC coil operation on DIN rail mounting. This relay features a 11A contact rating and is suitable for industrial control applications requiring dual-pole, dual-throw switching functionality.

The 2903281 is classified as obsolete. Identifying equivalent substitute parts is necessary to maintain system functionality and ensure continued availability for replacement and new installations where this relay specification is required.

Substiute Parts

2903281

Phoenix ContactIn Stock: 8222903281 Datasheet

Current PartRFQ

2903278

Phoenix ContactIn Stock: 9322903278 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 2903281 is limited by the following critical parameters:

• Coil Voltage: Must be 24VDC to maintain compatibility with existing control circuits
• Mounting Type: Must be DIN Rail to fit within the same mechanical envelope
• Termination Style: Must be Spring Terminal for direct connection compatibility
• Contact Material: Silver Nickel (AgNi) ensures consistent switching performance
• Operating Temperature Range: Must support -40°C ~ 60°C operation
• Coil Current: 56 mA establishes the control circuit load requirement

The Phoenix Contact 2903278 shares all critical parameters with the 2903281. However, the 2903278 features a 3PDT (3 Form C) contact configuration with a 10A contact rating, compared to the 2903281's DPDT (2 Form C) with 11A rating. This difference in contact form and current rating must be evaluated against specific application requirements.

Parameter Comparison

Engineering Selection Recommendations

The 2903281 is obsolete, making the 2903278 the active alternative within the Phoenix Contact RIF series. Both relays share identical coil voltage, switching voltage, coil current, mounting type, termination style, and operating temperature specifications.

The primary differences are contact configuration and current rating. The 2903278 provides three independent Form C contacts (3PDT) versus the 2903281's two Form C contacts (DPDT), with a 10A versus 11A contact rating respectively. Applications requiring exactly two switching poles with 11A capacity must evaluate whether the additional pole and reduced current rating of the 2903278 are acceptable for the intended circuit.

The 2903278 carries ROHS3 compliance, representing current regulatory alignment compared to the 2903281's RoHS compliance status. The 2903278 is also subject to REACH regulations, indicating its suitability for European market applications.

Frequently Asked Questions (FAQ)

Q: Can the 2903278 directly replace the 2903281 in all applications?

A: Direct replacement depends on circuit requirements. Both relays operate on 24VDC with identical coil current and switching voltage specifications. However, the 2903278 provides three switching poles instead of two, and has a 10A contact rating versus 11A. Applications using both poles at or near 11A may require circuit redesign.

Q: What is the significance of the contact form difference between DPDT and 3PDT?

A: DPDT (2 Form C) provides two independent switching circuits, each capable of switching between two positions. 3PDT (3 Form C) provides three independent switching circuits. The 2903278's additional pole may be unused in applications designed for DPDT operation, but the relay will function correctly.

Q: Are there packaging differences between these relays?

A: The 2903281 is listed with packaging designation "-" while the 2903278 is supplied in Bulk packaging. Both use DIN Rail mounting with Spring Terminal connections, ensuring mechanical compatibility in standard control enclosures.

Q: How do the compliance certifications differ?

A: The 2903281 is RoHS Compliant. The 2903278 is ROHS3 Compliant and REACH Affected, indicating compliance with current European environmental and chemical regulations. For applications subject to REACH requirements, the 2903278 is the appropriate selection.

Q: What is the inventory status of these parts?

A: The 2903281 (obsolete) has 758 pieces in stock. The 2903278 (active) has 893 pieces in stock, providing greater availability for ongoing procurement needs.